圖像化QR Code輸出條件與辨識率分析

Abstract

科技發展伴隨著行動裝置與網路的普及，二維條碼中的QR Code（Quick Response Code）已成為串聯網路與實體世界的主要媒介，如今QR Code被廣泛地應用於行銷或廣告用途，所以美化發展也越來越受重視，其中圖像化QR Code因具備視覺有意義的外觀，漸漸成為相關研究的重點。QR Code常出現於物聯網「一物一碼」的應用，然而若圖像化QR Code要配合一物一碼之實體輸出，則輸出條件能否使得圖像化QR Code被手機掃描，將會是重要關鍵，但鮮少研究針對此問題進行探討，故此為本研究之目的。本研究使用版本六之QR Code（41x41個模組, module），容錯率為H等級（容許30%錯誤）。首先選擇4張不同的影像產生圖像化QR Code，再使用雷射印表機與數位印刷機各輸出3個不同尺寸，得24張影像。輸出品透過600PPI掃描器取像，透過軟體分析24張圖像化QR Code影像中的module以及codeword之錯誤數據。為了降低錯誤以提升辨識率，進行5種不同數值的階調處理，以及調整8個不同參數之加密強度來得到圖像化QR Code，最後再測試印刷之穩定度。經實驗結果顯示，使用數位印刷機輸出的圖像化QR Code辨識效果優於雷射印表機，另一方面發現多數情況下資訊點錯誤情況之False-black(資訊點白點誤判黑點)多於False-white(資訊點黑點誤判白點)。經過階調調整之後，兩種錯誤情況皆得到改善，而加密強度的提升更能有效降低錯誤率。最後，本實驗找出圖像化QR Code錯誤情況，並透過調整圖像化QR Code使其能被手機掃描。本研究找出圖像化QR Code使用雷射印表機與數位印刷機之下辨識率的差異，並且透過調整圖像化QR Code之後使辨識率提升，可供QR Code與印刷相關研究作為參考。With the popularity of mobile devices and network, QR Code (Quick Response Code) have flourished and have been widely used as the main medium which can connected the virtual as well as the physical world. Today, QR Code is widely used for marketing or advertising purposes, so the development of beautification is also receiving attention. Among the developments, the Graphic QR Code has gradually become important because of its visual appearance. Also, QR Code often used in the application of the IoT (Interment of Things). However, the printing conditions could affect the Graphic QR Code’s recognition, which can caused some inconveniences in practical uses, but much less research had discussed on this issue. Therefore, this research focused on those output condition problem. In this research, the 6th version QR Code with H level (which with 30% fault tolerance) was adopted. First, there were four images had been formed to 4 Graphic QR Codes. Second, they were printed out with the laser printer and the digital printer with three sizes, 24 graphic QR Codes in total. Next, all Graphic QR Codes were scanned by 600 PPI (Pixels Per Inch) and then tested the module and codeword error rate. Finally, the tone-adjustment and different encode-strength were used to eliminate those error rate. According to the result, the recognition of printed Graphic QR Code by the digital printer was superior to the laser printer. In the other hand, through the adjustment of tone-adjustment and encode-strength, the recognition rate could enhanced. This research can be provided as the reference of QR Code and printing related studies.